Question

I’m trying to query a table and get the results into a variable. With the variable results do another select query using the variable details as the filter.

So far:

DECLARE @storeIds int    
SET @storeIds = (SELECT StoreID FROM Store WHERE ParentStoreID=9)

--print @storeIds

SELECT c.FirstName, c.LastName, c.CustomerId, r.StoreID
FROM Consumer AS c
    INNER JOIN Purchases AS r ON c.CustomerId= r.CustomerId
WHERE r.StoreID = @storeIds
   -- (r.StoreID = 9) OR
   -- (r.StoreID = 10) OR
   -- (r.StoreID = 11)
GROUP BY c.FirstName, c.LastName, c.CustomerId, r.StoreID
ORDER BY c.FirstName

I get an error:

Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.

Answer 1

Unless you particularly want the @StoreIds variable elsewhere you could just amend your WHERE clause to:

WHERE r.StoreID IN (SELECT StoreID FROM Store WHERE ParentStoreID = 9)